Why is Geoserver downsampling my geotiff?

Question

I created a KML file from a geotiff using Geoserver, but the image looks really pixelated in Google Earth. The image is a geotiff and is only around 7MB. Any reason why it might look so pixelated?

Answer 1

Please do inner tile and add overviews to your tiff file, see here: http://demo.geo-solutions.it/share/foss4g2011/gs_steroids_sgiannec_foss4g2011.pdf

Answer 2

Found this on a mailing list and I think it is should address your situation as well:

If you have .tif and .tfw files then you probably do not have geotiff, just a plain tiff with world file for georeferencing. Problem is that world file does not tell the projection. You can try two options:

• Convert image to GeoTIFF with gdal_translate. Command to use could be like gdal_translate -of GTiff -a_srs epsg:4326 -co tiled=yes test.tiff georeferenced.tif
• Or create a .prj file which contains the information about the projection in the ESRI style and place it to the same place as .tiff and .tfw

You might want to convert it to a real GeoTIFF as suggested in the list and see if it works.

As for the pixelated images, you can try tweaking the WMS Raster Rendering options.

Try using the bilinear or bicubic interpolation. It should be able to address your pixelation issues.